logic v.s. knowledge

I had always believed that logic is the uttermost important thing in the world. as for knowledge about the nature around me, what I need is just only a few pricinples so that I could build up the whole masion of my knowledge by logic and let it guide my action. I still have some of the principle in my mind: treasuring life, be breave, be modest, keep my word.
it is not until recently that I found a big problem in my doctrines: there are too many of them!! too many to remember and what's more, some are even contradicting with each other. for example, be prudent v.s. be brave, when carrying out a new business plan or try something new, these two are always contradicting. Yes, one may say that one can find the balance in between, but how? need another principle, called the principle of the between and adding it to the divine pantheon which left no place for one more? moreover, even if one thinks one find the balance, how can he know there is no other better way to do? so here, principle do not work at all, the same pity for the pure logic who loses his ground!

weep for my logic!
to be continued